Non magnum 330's dukes or victor. Never let me down. Don't miss many, don't self destruct like the magnums I tried. No broken bones, don't need a setting tool. Trapping beavers, no otters in my waters. Maybe if I had otters and troubles with misfires or catching too far back on the body I would try 280. Just my opinion guys.

My father used 330's exclusively. Everything was set up to use them back in the 1960's. I followed the same practice.
330's are plentiful and have a strong and firm catch on all beaver, lynx and wolf. By managing where I put my dog, so that it doesn't mark the valuable back of the beaver, I have had no issues with the 330. I view the 330 like hunters view the 30-06; it is efficient in its performance and everyone has some to trade or has extra parts to fix yours.
More traps of different sizes means more of a different stock you must keep in the trapping shack.
Here's wishing you well in all your trapping endeavors.